floor


function
<cmath>
     double floor (      double x );
      float floor (       float x );
long double floor ( long double x );

Round down value

Returns the largest integral value that is not greater than x.

Parameters

x
Floating point value.


Return Value

The largest integral value not greater than x.

Portability

In C, only the double version of this function exists with this name.

Example

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/* floor example */
#include <stdio.h>
#include <math.h>

int main ()
{
  printf ("floor of 2.3 is %.1lf\n", floor (2.3) );
  printf ("floor of 3.8 is %.1lf\n", floor (3.8) );
  printf ("floor of -2.3 is %.1lf\n", floor (-2.3) );
  printf ("floor of -3.8 is %.1lf\n", floor (-3.8) );
  return 0;
}


Output:

floor of 2.3 is 2.0
floor of 3.8 is 3.0
floor of -2.3 is -3.0
floor of -3.8 is -4.0


See also

ceil Round up value (function)
fabs Compute absolute value (function)
modf Break into fractional and integral parts (function)